When starting with basic courses in acoustics, you will learn that there are two so called basic or fundamental waves, longitudinal waves (compressional waves) and transversal waves (shear waves). And in dead these waves are fundamental! All Vibration in gases, fluids and structures can be composed of these two wave types. To say it somewhat simplified, you can only compress a portion of mass (i.e. change its volume) or deform the shape of the portion of mass without changing its volume (transversal motion). 


The example demonstrates these two wave types.


Keywords:

     longitudinal wave
     compressional wave
     transversal wave
     shear wave
